Internet Engineering Task Force (IETF)                          J. Arkko
Request for Comments: 5737                                      Ericsson
Updates: 1166                                                  M. Cotton
Category: Informational                                        L. Vegoda
ISSN: 2070-1721                                                    ICANN
                                                           January 2010


            IPv4 Address Blocks Reserved for Documentation

Abstract

  Three IPv4 unicast address blocks are reserved for use in examples in
  specifications and other documents.  This document describes the use
  of these blocks.

Status of This Memo

  This document is not an Internet Standards Track specification; it is
  published for informational purposes.

  This document is a product of the Internet Engineering Task Force
  (IETF).  It represents the consensus of the IETF community.  It has
  received public review and has been approved for publication by the
  Internet Engineering Steering Group (IESG).  Not all documents
  approved by the IESG are a candidate for any level of Internet
  Standard; see Section 2 of RFC 5741.

  Information about the current status of this document, any errata,
  and how to provide feedback on it may be obtained at
  http://www.rfc-editor.org/info/rfc5737.

Copyright Notice

  Copyright (c) 2010 IETF Trust and the persons identified as the
  document authors.  All rights reserved.

  This document is subject to BCP 78 and the IETF Trust's Legal
  Provisions Relating to IETF Documents
  (http://trustee.ietf.org/license-info) in effect on the date of
  publication of this document.  Please review these documents
  carefully, as they describe your rights and restrictions with respect
  to this document.  Code Components extracted from this document must
  include Simplified BSD License text as described in Section 4.e of
  the Trust Legal Provisions and are provided without warranty as
  described in the Simplified BSD License.





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1.  Introduction

  This document describes three IPv4 address blocks that are provided
  for use in documentation.  The use of designated address ranges for
  documentation and examples reduces the likelihood of conflicts and
  confusion arising from the use of addresses assigned for some other
  purpose.

  [RFC1166] reserves the first of the three address blocks,
  192.0.2.0/24.  The other two address blocks have recently been
  allocated for this purpose, primarily to ease the writing of examples
  involving addresses from multiple networks.

  Other documentation ranges have been defined in the IETF, including
  the IPv6 documentation prefix [RFC3849] and example domain names
  [RFC2606].  Documentation also makes use of the ranges reserved in
  [RFC1918].

2.  Terminology

  The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
  "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
  document are to be interpreted as described in BCP 14, [RFC2119].

3.  Documentation Address Blocks

  The blocks 192.0.2.0/24 (TEST-NET-1), 198.51.100.0/24 (TEST-NET-2),
  and 203.0.113.0/24 (TEST-NET-3) are provided for use in
  documentation.

4.  Operational Implications

  Addresses within the TEST-NET-1, TEST-NET-2, and TEST-NET-3 blocks
  SHOULD NOT appear on the public Internet and are used without any
  coordination with IANA or an Internet registry [RFC2050].  Network
  operators SHOULD add these address blocks to the list of non-
  routeable address spaces, and if packet filters are deployed, then
  this address block SHOULD be added to packet filters.

  These blocks are not for local use, and the filters may be used in
  both local and public contexts.










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5.  The Status of 128.66.0.0/16

  Note that 128.66.0.0/16 has been used for some examples in the past.
  However, this block did not appear in the list of special prefixes in
  [RFC3330] or its successors, and the block is therefore not reserved
  for any special purpose.  The block can be used for regular address
  assignments with caution.

6.  Security Considerations

  This document has no security implications.

7.  IANA Considerations

  IANA has recorded the allocation of the three address blocks in the
  IPv4 address registry.  No end party is to be assigned these
  addresses.

8.  References

8.1.  Normative References

  [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
             Requirement Levels", BCP 14, RFC 2119, March 1997.

8.2.  Informative References

  [RFC1166]  Kirkpatrick, S., Stahl, M., and M. Recker, "Internet
             numbers", RFC 1166, July 1990.

  [RFC1918]  Rekhter, Y., Moskowitz, R., Karrenberg, D., Groot, G., and
             E. Lear, "Address Allocation for Private Internets",
             BCP 5, RFC 1918, February 1996.

  [RFC2050]  Hubbard, K., Kosters, M., Conrad, D., Karrenberg, D., and
             J. Postel, "INTERNET REGISTRY IP ALLOCATION GUIDELINES",
             BCP 12, RFC 2050, November 1996.

  [RFC2606]  Eastlake, D. and A. Panitz, "Reserved Top Level DNS
             Names", BCP 32, RFC 2606, June 1999.

  [RFC3330]  IANA, "Special-Use IPv4 Addresses", RFC 3330,
             September 2002.

  [RFC3849]  Huston, G., Lord, A., and P. Smith, "IPv6 Address Prefix
             Reserved for Documentation", RFC 3849, July 2004.





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Appendix A.  Acknowledgments

  The authors would like to offer a special note of thanks to APNIC,
  which nominated 198.51.100.0/24 and 203.0.113.0/24 for this purpose.
  The authors would also like to acknowledge that this document
  inherits material from [RFC3849].

  The authors would also like to thank Geoff Huston, Peter Koch, Ulf
  Olsson, John Klensin, and others for interesting discussions of this
  topic.

Authors' Addresses

  Jari Arkko
  Ericsson
  Jorvas  02420
  Finland

  EMail: [email protected]


  Michelle Cotton
  Internet Corporation for Assigned Names and Numbers
  4676 Admiralty Way, Suite 330
  Marina del Rey  90292
  United States of America

  Phone: +1-310-823-9358
  EMail: [email protected]
  URI:   http://www.iana.org/


  Leo Vegoda
  Internet Corporation for Assigned Names and Numbers
  4676 Admiralty Way, Suite 330
  Marina del Rey  90292
  United States of America

  Phone: +1-310-823-9358
  EMail: [email protected]
  URI:   http://www.iana.org/










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